WASHINGTON (Reuters) - A Georgian-American businessman who met then-Miss Universe pageant owner Donald Trump in 2013, has been questioned by congressional investigators about whether he helped organize a meeting between Russians and Trump’s eldest son during the 2016 election campaign, four sources familiar with the matter said.

The meeting at Trump Tower in New York involving Donald Trump Jr. and other campaign advisers is a focus of probes by Congress and Special Counsel Robert Mueller on whether campaign officials colluded with Russia when it sought to interfere in the U.S. election, the sources said. Russia denies allegations by U.S. intelligence agencies that it meddled in the election and President Donald Trump denies any collusion.

The Senate and House of Representatives intelligence committees recently questioned behind closed doors Irakly Kaveladze, a U.S. citizen born in the former Soviet republic of Georgia, the sources said. He is a U.S.-based representative of Azerbaijani oligarch Aras Agalarov’s real estate firm, the Crocus Group.

The panels knew Kaveladze was at the June 9, 2016 meeting but became more interested in him after learning he also attended a private dinner in Las Vegas in 2013 with Trump and Agalarov as they celebrated an agreement to hold that year’s Miss Universe pageant in Moscow, the sources said.

Committee members now want to know more about the extent of Kaveladze’s contacts with the Trump family and whether he had a bigger role than previously believed in setting up the Trump Tower meeting when Trump was a Republican candidate for president.

The White House declined to comment. Mueller’s office also declined to comment.

Scott Balber, a New York lawyer who represents Kaveladze, confirmed that his client attended both the dinner in Las Vegas and the Trump Tower meeting but said he did not set up the second meeting. Trump’s son-in-law Jared Kushner, other Trump campaign aides, and Russian lawyer Natalia Veselnitskaya were also at that meeting.

Lawyer Balber also said the committees were only seeking Kaveladze’s input as a witness and were not targeting him for investigation.

“No-one has ever told me that they have any interest in him other than as a witness,” Balber said.

Lawyers for Trump Jr. and Kushner did not respond to requests for comment about their contacts with Kaveladze. A lawyer for President Trump declined to comment.

One photograph from the 2013 dinner, when Trump still owned the Miss Universe pageant, shows Agalarov and his pop singer son Emin along with Trump, two Trump aides and several other people at the dining table. Another shows Kaveladze standing behind Trump and Emin Agalarov as they speak.

The pictures were found by a University of California at Irvine student and blogger Scott Stedman, who posted them on Nov. 22. Aras Agalarov is a billionaire property developer in Russia who was awarded the Order of Honor by Russian President Vladimir Putin.

Several U.S. officials who spoke on condition of anonymity said Mueller’s team and the committees are looking for any evidence of a link between the Trump Tower meeting and the release six weeks later of emails stolen from Democratic Party organizations.

They are also trying to determine whether there was any discussion at the New York meeting of lifting U.S. economic sanctions on Russia, a top priority for Putin, the officials said.

Rob Goldstone, a British publicist, told Trump Jr. ahead of the New York meeting that Russian lawyer Veselnitskaya would be bringing damaging information about donations to a charity linked to Trump’s Democratic rival Hillary Clinton, according to emails later released by Trump Jr.

Trump Jr. initially said the meeting was about Russian adoptions but later said it also included Veselnitskaya’s promises of information on the donations to the Clinton charity. He said he ultimately never received the information, although it was later posted on the Internet.

In a statement issued after meeting with the Senate Judiciary Committee on Sept. 7, Trump, Jr. said Goldstone and Veselnitskaya were in a conference room with him as well as Kaveladze and a translator.

Balber said Kaveladze attended expecting to serve as a translator, although he did not do so in the end because Veselnitskaya brought her own.